(a) Field of the Invention
The present invention relates to a method and apparatus for tracking a user's gaze point using a mobile terminal. More particularly, the present invention relates to a method and apparatus for tracking a gaze point of a user who gazes at a display of a mobile terminal.
(b) Description of the Related Art
With recent improvements in computer technology providing a wide range of new contents, a desire to conveniently use them is increasing. Therefore, to provide a more user friendly interface beyond interaction using general input interface equipment such as a keyboard and a mouse, research using various body information has been actively performed. Particularly, an interface using eye motion tracking can easily transfer an intention and perform efficient interaction even with a few motions, and thus function as a human friendly interaction means.
Initial researches that are related to user's gaze position tracking have tracked the user's gaze position using infrared ray light due to a limitation in performance of an existing camera. Because such a gaze position tracking system grasps a position of eyes in an entire face, accurately projects light to eyes, and calculates a relationship of light that is reflected from a periphery of a pupil and an iris, the gaze position tracking system was formed under an assumption that it fixes a user's motion in which only the pupil is moved.
Subsequently, as camera performance has been greatly improved and cameras are now formed with a small size, research on methods that do not use infrared rays light has been performed to solve a problem according to a user motion. Most of such research has extracted a plurality of characteristic points (eye, nose, and mouth) within the user face and has recognized the user's motion through a geometrical change between the characteristic points.
A distance between a user and a portable terminal display is an average of 35 cm (31.5 cm when Web searching), and when using the portable terminal, a case in which the user's image that is input to a front surface camera is not an entire face area is very frequent. Therefore, the above methods are inappropriate as a motion correction method for using a portable terminal. Conventionally, by determining a gaze position by extending a gaze that is calculated through motion correction to a monitor, a problem of generating a large error at an actual gaze position from a small error that is started from pupil motion detection has occurred.
Background technology of the present invention is disclosed at Korean Patent Laid-Open Publication No. 10-2000-0056563 (laid-open at Sep. 15, 2000).